Azo dyes



Patented Dec. 16, 1941 UNITED STATES Azo DYES Moses L. Crossley, Plainfield, N. J., assignor, by

mesne assignments, a. to

American Cyanamid (lompanyaNewaYork; N. Y., a corporation of Thisvinvention relates to new monazo dyes containing higher alkyl phenols as a component.

Many monazo dyes have been prepared in the past using phenol or methylated phenols as components. According to the present invention, it has been found that phenols having a longer alkyl chain give dyes of good shades with excellent properties such as milling, fastness to light and washing and the like.- While valuable dyes may be produced from phenols having as short an alkyl chain as three carbon atoms, the most importantdyes are; those (which contain 1 alkyl phenols. with still longer hydrocarbon chain, particularly the amyl and octyl phenols The new dyes of the present invention may 5 contain solubilizing groups and it is an important advantage. ofthisform of the invention that many of the vdyes containing solubilizing groups 3 will dye cellulose acetate aswell as animal fibers. This-isa ,very important property of certain'of 0 the colors falling under the presentinvention because as is well known, the dyeing of cellulose acetate" presents; a serious. problem 7 and has hitherto required special insoluble dyes whichf wereused in a dispersed for-m thus greatly1reduc-1 ing the choice of shades which could be obtained satisfactorily with cellulose acetate and requiring a special, dyeing procedure.

The soluble dyes of the present invention also hayeanimportant property of great light fast: ness-and fastness to washing evenin sea water. This makesitpossible to use the soluble dyes r re tn t o hichcmusb i st Sea t r s; Qr sam e 1 bat n su ts- A:w da ri t toix i zoi m o nds, w i h canr fi becoupled vith the higher alkyl phenols of the; present invention of course will produce dyes having a Wide range of shades and the solubility of the resulting dyes will depend on the nature of the diazo component. ,Thus, for example, 40 phenyl and naphthylndiazonium; salts as well as their nitro, chlor and hydroxy derivatives which do not contain solubilizing groupsyvill give water insoluble azo dyes with the higher alkyl ph'enols of the present invention. These products are in general soluble in organic solvents such as alcohols and aromatic hydrocarbons giving colored solutions usually varying in shade from yellow to bluishreds, The solubility .in aromatichydrocarbons .v is arvery important property, of these 50 dyes: and whileI do. not wish to limitiny inventionito Zanyparticular theory, I believe. thatthe; increased solubility inaromatic hydrocarbons is in considerable part due Ito the,long,alkyl chaint di z o po e may lsow' ain metals 1.

i ss-,. t a i iiror h r nieid n r solved in lqliters 0f concentrated hydrochloric 4 acid andjth'en added with stirring: to 1,500-liters of agnnrture o f ic e and Water. To this mixture} is added 21 lag oi sodium nitrite in the 'rqim of a 20% solution, maintaining the temperature "at 10-15 C. A positive starch'iodide test "holding for ten minutes is obtained A solution of tertiary amyl phenol is then prepared by heating 18 kg. of the phenol with 14 kglof caustic in 1,000 liters of water. This solution is cooled to 0 C. with ice and the above diazo solution added I slowly, maintaining the temperature during the coupling at 0 C. The reactionmixture is maintained strongly alkaline to phenolphthalein by the addition of caustic soda solution when necessary. The dye separated, being insolublewin water, is filtered, washedand dried, It isa red= brown powder quitesolublein benzene; sparingly. soluble in: methyl. alcohol. Itcolors nitrocellulose lacquer-yellow; It has the folloWingstiuctural formula; I

Instead of using para, tertiary amyl phenol the other isomeric amyl; phenols may be em- I ployed,,. giving;dyes having very similar shades,

EXAMPLE 2 of the phenol with 14 kg. of caustic in 1,000 liters of water. This solution is cooled to 0. C. with ice and the above diazo solutionadded slowly, main;

OCHs

O sH17- EXAMPLE 3 17.3 kg. of sulfanilic acid is diazotized in the usual way and coupled with a tertiary amyl phenol solution containing 18 kg. of the amyl phenol dissolved in a caustic solution containing 14 kg. of caustic in 1,000 liters of water. The phenol solution was previously cooled to C. with ice and the coupling is conducted by adding the diazo to the phenol solution, maintaining the temperature between 0 and 5. The reaction product is maintained alkaline to phenolphthalein by adding caustic when necessary. The product is salted out with sodium chloride, filtered and dried. It is soluble in water and dyes Wool, silk and cellulose acetate yellow. The dye hasthe following structural formula:

CsHn

An amount of sodium naphthionate containing 49 parts of real is dissolved in 750 parts of water. To this solution is added sufficient sodium nitrite to furnish about 14 parts of real nitrite. This entire solution is then added to an aqueous hydrochloric acid solution containing 64 parts of concentrated hydrochloric acid in 500 parts of water. The mixture is cooled by means of ice to C. and this temperature maintained throughout the diazotization. The diazo solution is then added to a solution of para tertiary amyl phenol containing 36 parts of the phenol dissolved in 2,000 parts of water containing 28 parts of caustic. The coupling was conducted at 0 C. It is maintained strongly alkaline to phenolphthalein throughout the reaction. The excess alkalinity at the end of the coupling is neutralized with acetic acid until it just showed a negative test for alkali with benzo purpurin paper. It is then salted, filtered and dried. The product is soluble in water and dyes wool and silk yellow to orange tones of color. It also dyes cellulose acetate yellow. It has the following structural formula:

Other isomeric amyl phenols may be substituted aaea n for the para tertiary amyl phenol and similar products be obtained.

EXAMPLE 5 An amount of H acid equivalent to 128 kg. of real is dissolved in 1,500 liters of water, and the solution is made slightly alkaline with 16 kg. of caustic soda. To this solution is added 400 liters of normal nitrite solution. The entire mixture is then added gradually to a cold concentrated hydrochloric acid solution containing 224 liters of concentrated hydrochloric acid. The reaction is maintained at a temperature of approximately 10 C. A solution of ortho tertiary amyl phenol is prepared by dissolving 38 kg. of the phenol and 52 kg. of caustic in 2,000 liters of water. This was cooled to 0 and the diazo solution added slowly. When the coupling is complete the dye is precipitated by the addition of salt. It is then filtered and dried. It is water soluble and dyes wool and silk yellowish tones of brown but does not dye cellulose acetate. It has the following structural formula:

OHN N H035 SO3H (351111 erties.

EXAMPLE 6 An amount of ortho aminophenol para sulfonic acid equivalent to about '76 parts real is dissolved in 1,500 parts of water containing sodium carbonate sufiicient to dissolve the product. The solution is then acidified with 156 parts of concentrated hydrochloric acid and cooled with ice to 0 C. Sodium nitrite is then added slowly until a positive endpoint for completion of the diazotization is obtained and remains positive for 10 minutes. A solution of ortho tertiary amyl phenol is prepared by dissolving about '72 parts of the phenol in water containing 56 parts of caustic. The solution is cooled to 0 and the coupling conducted by running the diazo slowly into the phenol solution at a uniform rate. When the coupling is complete the dye is salted out with sodum chloride, filtered and dried. It is soluble in water, producing interesting tones of yellow on wool, silk and cellulose acetate. The dye has the following structural formula:

03H OCsHn EXAMPLE 7 The diazo product obtained by treating 27.5 kg. of para nitraniline in 50 liters of Water with 64 liters of concentrated hydrochloric acid diluted with 500 liters of water and diazotized with 14 kg. of nitrite at 0 C. is filtered and the solution added within 10 minutes to a para tertiary amyl phenol solution prepared from 36 kg. of the phenoli andifia ;kg;'of caustic in'LOOOlitersiof water. The coupling is carried out at 0.: The

excess alkalinityis'adjusted to a negative test on benzo purpurin paper and the dye salted out, filtered and dried. It is insoluble in water; soluble in benzene, alcohol and nitrocellulose lacquer, giving greenish tones of yellow. The product has the following structural formula:

Table No. Formula Color 1 N=N Orange.

os u S OaH 2 N N Orange red.

CaHn

S Cali 3 N N Yellowish orange.

4 N N Reddish orange.

0 CH3 OH 5 N :N Orange red.

(751111 N (CH3):

6 N: Orange.

7 N=N Yellowish orange.

8 N N\ Yellowish orange.

0 O OH CsHn No. Formula Color 9 N=N Orange.

CBHII" 10 CH3 Orange.

-GH3 OH 11 N OH Orange.

SOaH

EH11 12 N=N Red.

& Q-Cslin H 13 Red.

14 N N Orange.

CaH11 15 CH3 Reddish orange.

-N=N\ S 03H I claim:

1. A monazo dye having the following formula in which R1 is an aromatic radical free from azo groups and R2 is an alkyl group having more than four carbon atoms.

2. A monazo dye having the following formula CaHu in which R1 is an aromatic radical free'from azo groups.

3. A mohaZo dye having the following formula in which R1 is an aromatic radical free from azo OH groups.

MOSES L. CROSSLEY. N=NR1 Certificate of Correction Patent No. 2,266,413. December 16, 1941. MOSES L. CROSSLEY It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows: Page 3, first column, lines 66 to 69, for that portion of Formula No. 7 reading read lines 71 to 75, Formula N o. 8, and second column, lines 5 to 9, Formula No. 9, for

read

C sHuand lines 34 to 37, Formula N o. 13, for

read

and lines 38 to 43, Formula N o. 14, for

O H CsHn- CaHi and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 3rd day of March, A. D. 1942.

[SEAL] HENRY VAN ARSDALE,

Acting Commissioner of Patents. 

